Diesel engine



Sept. 18, 1934. STRQUD' I 1,974,088

DIESEL ENGINE Filed June 15. 1952 2 Sheets-Sheet 1 IN VEN TOR Sept. 18,1934.

F. H. STROUD DIESEL ENGINE Filed 'Jun e 13 19:52 2 Sheets-Sheet 2HSi-rbud IN VENT OR n W n A .5 a m H n 4 Mn QN an S Q E 2 3 a PatentedSept. 18, 1934 PATEN'll OFFICE DIESEL ENGINE Francis H. Stroud, Seattle,Wash., assignor to Johnson Manufacturing 00., Seattle, Wash., a

corporation of Washington Application June 13, 1932, Serial No. 616,764

7 Claims.

My invention relates to internal combustion engines of the Diesel type.

One of the principal objects of my invention r is to devise an engine ofthis type which shall be extremely simple and compact, and which inparticular shall achieve these objects by elimination of valve gear ormoving parts especially intended for the control of the air.

A further object is the provision of a rigid and practical construction,whereby weaving and vibration oLthe engine at all speeds shall bepractically eliminated. It is a further object to provide an engine ofthis type which, by reason of its simplicity, compactness and theelimination of various working 1 ent is preferred by me.

v Figure 1 is aside elevation, with parts broke away and. shown insection, illustrating such an engine.

Figure 2 is a vertical axial section through v: one of a pair ofcylinders in such an engine.

' Figure 3 is an elevation of the block wherein are formed thecompression chambers, substantially on the line 3-3 of Figure 2, andFigure 4 is a transverse horizontal section substantially 'on the line4-l of Figure 2.

Figure 5 is a fragmentary vertical axial section through the secondcylinder of a pair, the first of which is illustrated in Figure 2, butshowing" parts advanced by a quarter of the Whole cycle.

The major engine parts, as herein shown, comprise a composite-cylinderincluding the working section 1, the cylinder head 10 secured thereon,the block 2whereon the working section rests, and which in turn restsupon the bed plate 3' to form the crankcase. The working piston 11 isreciprocable in the bore 12 of the cylinder 1 to open the air inlet port13 and the exhaust port 14 at the bottom of the pistons stroke. Securedto the bottom of the skirt of the Working piston 1 is a compressionpiston 4 reciprocable within the compression section of the compositecylinder defined by the bore 20 of the: block 2. The connecting rods 30connect .55 the "stepped pistons with the crank shaft 31.

to operate in alternate manner.

(Cl. 12359) 7 r I prefer that the crank shaft be balanced, as indicatedby the balancing members 32.

The block 2 is divided horizontally by a partition 21, thus defining anupper chamber 22 and a lower chamber 23. Valves 5 and 50, which may bealike and which may constitute simple check valves, control inlet of airinto the respective chambers 22 and 23. Preferably the air is screenedcoming through the aperture at 51. The block 2 may also be partitioned,as indicated at 24 (see Figure 4), vertically from top to bottom, toseparate those chambers 22 and 23 which pertain to each pair ofcylinders, and thus each pair of cylinders cooperates and may bedesignated No. 1' and No. 2 cylinders, or, for convenience, cylinders Aand B (see Figures 3 and 4) Cylinder A, the No. 1 cylinder, has a port25 at its upper end which communicates directly with the upper chamber22. Cylinder B, or .No. 2 cylinder of the pair, has a port 26 whichdischarges through a downwardly extending passage 26' into the lowerchamber 23. From the upper chamber 22 a port 27 affords communicationwith a passage 17 in the cylinder 1, the purpose of which .will appearhereafter, but which, itmay be stated, leads eventually to dischargewithin the cylinder 1, that working section which pertains'toth'ecylinder B. From the lower chamber 23 a passage 28 leads to a port 28corresponding to the port 27 and communicating with the port 17 of theworking section which corresponds to the cylinder A, or No. 1 cylinder.

As is explained in my copending application Serial No. 616,765, filedJune 13, 1932, the working piston 11 has a chamber 15 formed thereinimmediately beneath its working head, this chamber affording a throughpassage between the passages 17, which are in effect the sources of airunder pressure for the individual cylinders, at one side of the cylinder1, and a port 16 which, being in communication with the port '13,effects a 'by-pass of the gas when the piston is at the bottom of itsstroke, so that at this time, and only. at this time, air under pressurein the passage 17 is admitted through the chamber 15, the ports 16 and13, into the bore 12, forcing out the spent gases through the nowuncovered exhaust port 14.

The paired pistons of No. 1 and No. 2 cylinders, or those designated Aand B, are arranged One is at the top of its stroke when the other is atthe bottom, and vice versa. Considering the No. 1 or A piston to be atthe bottom of its stroke, as seen in Figures 1, 2 and 4, air which waspreviously compressed in the lower chamber 23 is permitted to pass intothe bore 12 to scavenge it, as previously explained. The piston, uponrising, covers the ports 13 and 14, traps the air therein, and furthercompresses it. At the same time the annular compression piston 4, risingin its bore 20, compresses air which is in this bore by virtue of thefree communication between this bore and the upper chamber 22 throughthe port 25. This air, of course, has been drawn in past the check valve5, but upon the commencement of the compression stroke of thisparticular piston l the valve 5 closes and the compression proceeds, inthis bore and also in the communicating chamber 22.

This upper chamber 22, it will be remembered, was in free communicationwith the passage 17 for cylinder B through the port 27. However, theworking piston in this cylinder B has started downward on the powerstroke, but has not yet uncovered its ports 13 and 14., nor have theports of its through passage 15 come into com munication with therespective ports 16 and 1'7. In consequence, there is no escape ofpressure from the upper chamber 22. When the piston B does reach thebottom of its stroke, the gas compressed in the upper chamber 22 is nowreleased through the piston B and into the cylinder B, and as thispiston now starts upward, its piston 4 commences to compress the airwhich is in its bore by virtue of the free communication through thepassage 26 and port 26 communicating with the lower chamber 23. This airhad been drawn in past the check valve 50, but as compression commences,the valve 50 closes, and as in the previous instance, the compressioncannot escape through the open port 2'] for the reason that the pistonin cylinder A has started downward on its power stroke, but has notbrought its ports into communication with those in its own cylinder.

From this it can be seen that simple check valves 5 and 50, and thearrangement of ports in the block 2, in the cylinder 1 and in the piston11, very simply control the compression and admission of air, and ofcourse, the discharge of the spent gases.

Because of the passages 26' and 28 extending through the upper chamber22, it is best to dis pose the horizontal partition 21 somewhat morethan half way down from the top of the block 2. .Thus the volumes of thetwo chambers 22 and 23 may be equalized to the end that the compressionin each of them for a given piston displacement is the same.

The block 2 is well braced by the partitions .and passages Which havebeen described, and by the several bores 20 extending therethrough. Nospecial pipe fittings or connections are required; machine work isreduced to a minimum. The working sections 1 are readily supported uponthis block, and the block in turn is readily and directly connected tothe bed plate 3. All may be locked together by the long bolts 6. Thisforms a simple and rigid construction which practically eliminatesweaving, and because the crank shaft is balanced, and there is no Valvegear rotating at high speed, offset from the general vertical plane ofthe engine, vibration is cut down to the minimum, and for all practicalpurposes is eliminated. This is a factor of large importance, adaptingthe engine for use upon vessels, upon steam shovels, logging equipment,

and the like, where vibration is destructive to equipment and harmful tothe operator or to those on board a vessel.

What I claim as my invention is:

1. An engine having its cylinders arranged in pairs, each cylinder of agiven pair including a working and a compression section, and saidengine includinga hollow block having an upper compression chamberfreely communicating with the compression section of one cylinder of agiven pair and adapted to communicate with the working section of theother cylinder of such pair; and said block having also a lowercompression chamber freely communicating with the compression section ofsuch other cylinder of the pair and adapted to communicate with theworking section of the first cylinder, and working and compressionpistons reciprocable within the respective cylinders.

2. An engine having composite cylinders arranged in pairs, each of saidcomposite cylinders comprising a working section and a compressionsection in coaxial arrangement, stepped working and compression pistonsreciprocating in the respective cylinders, said engine including ahollow block partitioned to-define lower and upper compressionchambershaving checkvalve-controlled inlets, the working section of onecomposite cylinder of a given pair being in free communication with thelower compression chamber at such time as the working piston of suchcylinder is at the bottom of its stroke, and the upper end of thecompression section thereof being in free communication at all timeswith the upper compression chamber; and the working section of the othercomposite cylinder of such given pair being in free communication withthe upper compression chamber at such time as the working piston of suchcylinder is at the bottom of its stroke, and the upper end of thecompression section thereof being in free communication at all timeswith the lower compression chamber; and means to effect reciprocation ofsaid pistons in alternate manner, thereby to compress air in eachcompression section and associated chamber for timed discharge into thepaired working cylinder.

3. In an engine, a hollow block partitioned to define an upper and alower chamber having outlet ports, and said block also having cylindersarranged in pairs, each cylinder including a compression section formedin said hollow block and extending through said chambers and a workingsection above and coaxial with the compression section, the upper end ofthe compression section of one composite cylinder of each paircommunicating with the upper chamber, and the working sectioncommunicating with the outlet port of the lower chamber; and the upperend of the compression section of the other composite cylinder of eachpair communicating with the lower chamber, and the working sectioncommunicating with the outlet port of the upper chamber;check-valvecontrolled inlets to the respective chambers, and

stepped working and compression pistons reciprocable in alternate mannerin the paired cylinders, to close the outlet from each chamber upon thecompression stroke of the piston in the compression chamber dischargingthereinto, until the end of the power stroke of the piston in the pairedchamber receiving therefrom.

4. An engine comprising a hollow block and having paired cylinders, eachcylinder including a compression section and a working section above andcoaxial with the compression ram section, said hollow block beingpartitioned to define upper and lower compression chambers, the workingsection of one cylinder of a pair being adapted to communicate with thelower compression chamber and the compression section of such cylinderalways freely communicating with the upper compression chamber; and theworking section of the other cylinder of such pair being adapted tocommunicate with the upper compression chamber and the compressionsection of such other cylinder always freely communicating with thelower compression chamber; and working and compression pistonsreciprocable within the respective paired cylinders to controlcompression and discharge of air within the chambers.

5. An engine of the type described comprising a hollow block and havingtwo or more composite cylinders disposed in pairs, each cylinderincluding a compression section defined by boring said hollow block anda working section adapted to be supported on said block coaxially withthe compression section, the block being interiorly partitioned todefine upper and lower compression chambers, the compression sectionshaving open discharge ports, that of one composite cylinder of a givenpair communicating directly with the upper chamber, and a passageextending from the compression section port of the other compositecylinder of such given pair through the upper chamber and the partitionto afiord free communication with the lower chamher, the block beingported to afford communication of the working section of such othercomposite cylinder directly with the upper chamber, and the block havinga passage extending through the partition and the upper chamber toafiord free communication from the lower chamber to a port in the blockfor the working section of the first composite cylinder of such givenpair.

6. The combination of claim 5, and the block havingcheck-valve-controlled inlet ports for each chamber.

'7. The combination of claim 5, the partition being disposed nearer thebottom of the block to compensate in volume for the volume of thepassages through the upper chamber.

FRANCIS H. STROUD.

